Japan’s Prime Minister Shinzo Abe says Tokyo is “seriously concerned” about China’s claims in the East and South China seas.

Beijing claims almost all of the strategic South China Sea, which is also claimed in part by Taiwan, Brunei, Vietnam, Malaysia and the Philippines.

Japan has no claims in the South China Sea, but it is engaged in a territorial dispute with China over a group of islands in the East China Sea.

“I am seriously concerned about the continuing attempts to change unilaterally the status quo in the East and South China Sea,” Abe said at the regional summit of the 10-member Association of Southeast Asian Nations (ASEAN) in Laos on Wednesday.

“I hope that both parties to the dispute in the South China Sea will abide by the ruling handed down by the China-Philippines tribunal court, which legally binds the parties to the dispute, and it will lead to a peaceful settlement of the dispute,” Japan’s Foreign Press Secretary Yasuhisa Kawamura quoted Abe as saying.

In July, The Hague-based Permanent Court of Arbitration ruled that China’s claims to sovereignty over the disputed areas in the South China Sea or its resources “had no legal basis” in a case brought by the Philippines. The tribunal also accused Beijing of violating the Philippines’ economic and sovereign rights.

China, however, rejected the ruling, saying the court has no jurisdiction over the dispute.

ASEAN is a regional organization seeking to promote intergovernmental cooperation and facilitate economic integration among its member states.